The present invention relates to electronic devices, and more particularly, to battery backup for a electronic devices.
One drawback of conventional electronic devices is their need to have a secondary source of power so that they can remember certain important information stored in memory, for example the date and time, appointments, phone numbers, etc., in the event of a loss of main power. If the main power source device is a battery this can occur when the main battery is removed for replacement or recharging. If the main source of power is AC or DC power this can occur when there is a power failure or the device is accidentally unplugged. If the main power source is cut off for a short period of time, e.g., the battery is removed for immediate replacement, then a capacitor can be used to provide temporary power until the new batteries are inserted. However, if the batteries are removed for recharging then a capacitor is not sufficient because the batteries may sit out of the electronic device overnight or longer. In this case the designer of the electronic device generally provides a backup battery.
Electronic devices designed with backup batteries generally ship with the backup battery not installed in the device. The user must install the backup battery in the electronic device after they purchase the electronic device. This means that the packaging must contain the battery, the instructions must contain extra steps to show the user what to do with the backup battery, and the user must go through the extra step to install the backup battery.
It would be preferable if the electronic device could come from the factory with the backup battery already installed for the user. However, this is not done today because it is unknown how long the electronic device will sit on the store shelves before it reaches the customer, so by the time the customer takes it home, the backup battery might be drained of power. Some products provide a plastic tab that breaks the connection between the battery and the connectors, but in this case the user must still open the battery compartment, pull out the tab, and then put the cover back on.
Accordingly, it would be advantageous to be able to install the backup battery at the time of manufacture, but have the electronic device not drain the backup battery power until the user begins to use the electronic device.
The present invention is an electronic device for performing certain operations and includes a continuous operating unit providing operations benefitting from a backup battery for providing backup power to the continuous operating unit. The battery is installed in the electronic device at the time of manufacture and is connected to the continuous operating unit through a switch which is in the open position at the time of manufacture of the electronic device. An input device allows a user to input signals to the electronic device. A central processing unit is connected to the continuous operating unit and receives the input signals from the input device. The central processing unit contains firmware for performing the operations of the electronic device and the central processing unit closes the switch when a predetermined parameter is received from the input device. A main power source is connected to the central processing unit and the continuous operating unit for providing operating power to the central processing unit and the continuous operating unit. The invention also includes a method of operating an electronic device including executing an initialization procedure when an on/off control of a electronic device is actuated to an on condition, obtaining input information via an input device, analyzing the input information in a central processing unit to determine if a predetermined parameter is being input for the first time and closing a circuit between a backup battery and a continuous operating unit via a signal from the central processing unit when the predetermined parameter is input for the first time.